A mortar rifle, with a maximum range of 40 m on flat ground, is placed on the edge of a 20 m high vertical cliff overlooking the horizontal plain. Specify the distance horizontal R of mortar gun as a function of a (mortar elevation angle above horizontal)!

Maximize the height of the canon at 15 m and place the target 47.2 m. What initial horizontal speed must be to hit the target?

A bullet is launched with an initial velocity of 400 m / s and an elevation angle of 35 °. Calculate: a) the time it lasts in the air.b) The maximum height reached by the bulletc) The horizontal range of the bullet.

I am working on finding the inital velocity of a class II projectile and am having trouble determining the right amount of sig figs.  The taken measurements of the initial position of x goes to 4 sig figs, as well as the final position for y. With that being said, I am trying to find the initial velocity of x and y separately through trionometry. For example, if I have an equation for the initial velocity of x with an angle of 40, then  Vox=Vocos40 My question is, since the measured value for my angle is two significant figures, is my answer Vox=.76Vo also in two sig figs because it goes by the two significant figures from my measured angle, or should I go to four significant figures to match my measured values for x and y?