Beth added a piece of metal to a test tube that contained an acid. she observed bubbles forming on the surface of the metal. what does the formation of bubbles in this experiment show?

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination.at the turning point, how far is the second student from the destination?

The base of a 50-meter tower is at the origin; the base of a 50-meter tree is at (0, 50, 0). the ground is flat and the z-axis points upward. the following parametric equations describe the motion of six projectiles each launched at time t = 0 in seconds. (i) r (t) = (50 + t2)k (ii) r (t) = 2t2 j + 2t2k (iii) r (t) = 50 i + 50 j + (50 − t2)k (iv) r (t) = 2t j + (50 − t2)k (v) r (t) = (50 − 2t) i + 2t j + (50 − t)k (vi) r (t) = t i + t j + tk (a) which projectile is launched from the top of the tower and goes downward? at time t = , the projectile hits the ground at point (x, y, z) = . (b) which projectile hits the top of the tree?

Pl i beg u so much now propane burns in oxygen to produce carbon dioxide and steam. the unbalanced equation for this reaction is: c3h8 + o2 → co2 + h2o use coefficients to balance this equation. a) c3h8 + 3 o2 → 3 co2 + 4 h2o b) c3h8 + o2 → 3 co2 + 4 h2o c) c3h8 + 5 o2 → 3 co2 + 4 h2o d) 2 c3h8 + 5 o2 → 3 co2 + 4 h2o