Questions by okey43 - Page 69
Monthly commissions of first-year insurance brokers are $1,270, $1,310, $1,680, $1,380, $1,410, $1,570, $1,180 and $1,420. These figures are referred to as: A) raw data. B) histogram. C) frequency polygon. D) frequency distribution.
Riverbed Company uses flexible budgets to control its selling expenses. Monthly sales are expected to range from $180,200 to $212,000. Variable costs and their percentage relationship to sales are sales commissions 6%, advertising 5%, travel 3%, and delivery 2%. Fixed selling expenses will consist of sales salaries $37,100, depreciation on delivery equipment $7,420, and insurance on delivery equipment $1,060. Prepare a monthly selling expense flexible budget for each $10,600 increment of sales within the relevant range for the year ending December 31, 2022.
The first attempt to systematically characterize airfoil shapes performed by the National AdvisoryCommittee on Aeronautics (NACA), which was the predecessor organization to NASA. NACAcreated specifications for airfoils classified in the 4-digit series, 5-digits series, and 6-digit series,among others. The more complex 5- and 6-digit series will not be touched in this project. In theNACA four-digit series, a four-number designation is used to define each airfoil uniquely byspecifying the geometry. The first number of the 4 digits specifies the maximum camber, m, of theairfoil as a percentage of the chord length, c. The second number in the name specifies the position,p, of the maximum camber from the leading edge in tenths of the chord length. The camber is theamount of curvature in a wing. A wing with zero camber is symmetric. The last two digits togetherspecify the thickness, t, of the airfoil as a percentage of the chord. For example, a NACA 4515airfoil has a maximum camber of 4% of the chord, located 50% of the chord back from the leadingedge (halfway back), with a maximum thickness of 15% of the chord. As another example, aNACA 0012 airfoil is a symmetric airfoil, with a maximum thickness 12% of the chord.In this short project, you will analyze a viscous flow over the NACA 0012 and NACA4515 airfoils, as good examples of symmetrical and unsymmetrical airfoils, respectively. Pleaseperform all your calculations at a Reynolds number of =106 , using a number of panel nodesof 250, trailing edge to leading edge panel density ratio of 1. Then please answer the followingquestions:1. What are the angles of attack corresponding to zero lift in both cases? (0.5 points)2. What happens if you use a number of panel nodes of 100 (instead of 250) in yourcalculations? Does the angle of attack corresponding to zero lift change at all? (0.5 points)3. Plot p distributions over both airfoils at an angle of attack 5. (2 points)4. Use =0.1x106 (instead of =106) and replot p distributions over both airfoils atan angle of attack 5 . How does the reduced Reynolds number affect the p distribution?(2 points)5. Plot the variation of boundary layer thickness on the top surfaces of both airfoils as afunction of x-position at an angle of attack 10 . How do you compare the results of bothairfoils? (2.5points)6. Use =0.1x106 (instead of =106), and replot the variation of boundary layerthickness on the top surfaces of both airfoils as a function of x-position at an angle of attack10. How does the reduced Reynolds number affect the boundary layer profiles in bothcases? (2.5 points)7. Plot boundary layer velocity profiles at few different locations on the top surface of bothairfoils point at an angle of attack 10 and explain how separation occurs using theboundary layer velocity profiles. Which of the airfoils show early separation? (2 points)8. Plot and curves as a function of angle of attack for both airfoils (using a range ofangle of attack from 5 to 20). (2 points)9. What are the maximum and corresponding critical angle of attack in both cases?(1points)