176 ANSWERS. 



(16) On PoP lt P P 2 construct the parallelogram P P^P 2 and 

 draw P { S parallel to QP 2 , S being the intersection with the diagonal P^R. 



(18) Apply (16). 



Page 39. 



(i) For the angle 6 of the resulting rotation we have sin (0/2) 

 = J-V5/2 ; for the position of its axis /, sin(4/) = 2/Vs, sin(// 2 ) 



-Vtfc 



(3) 22. 



Page 47. 



(1) (a) 41 miles per hour ; (c) 19.1,8.2; (d) 10 h. 19 m. 



(3) At 2 h. 22 m. ; 203 miles from Detroit. 



(4) (a) 5.9; (2) 40.6; (c) 44; (/) 35.25; (e) 1093. 



(5) 15- 



(7) 185,000 miles per second. 



(8) (a) ih.; (b) 15 m. 



(9) 3of . 



( I0 ) 37i miles per hour. 



Page 53. 

 (0 H- 



(2) 32.186. 



(3) Nearly y L ft. per second per second. 



(4) 0.0034. 



Page 56. 



(1) (a) 96.6; () 402.5; (c) 144.9. 



(2) 0.275. 



(4) h =c\ / H -y -f 2 / 4- - J ; an approximate value is 



h = %- For a direct numerical computation, the method 



*('+**) 



of successive approximations may be used. Thus, neglecting the time 



