Afirecracker shoots up from a hill 160 feet high with an initial speed of 90 feet per second. using the formula h(t) = −16t2 + vt + s, approximately how long will it take the firecracker to hit the ground?

Aray of light traveling parallel to the principal axis of a concave mirror will be reflected through the mirror's

Aperson gives a shopping cart an initial push along a horizontal floor to get it moving, and then lets go. the cart travels forward along the floor, gradually slowing as it moves. consider the horizontal force(s) on the cart while it is moving forward and slowing. which of the following statements is correct? (a) both a forward and a backward force are acting on the cart, but the forward force is larger. (b) only a forward force is acting which diminishes with time. (c) both a forward and a backward force are acting on the cart, but the backward force is larger. (d) only a backward force is acting, no forward force.

How to tell if a molecule is polar or nonpolar with electronegativity