Astone is dropped in a river from a bridge. if it takes 4 seconds to reach surface of water ,calculate the depth of the water level from the bridge .also calculate the velocity with which the stone strikes on the water surface

Ineed the answer to question 1 , i’m desperate

At very high pressures, gases become and will eventually a) more dense; become hotter b) more dense; change to a liquid or solid c) less dense; combust d) less dense; turn into a liquid

In which situation is the acceleration of a car negative? question 5 options: a)the velocity of a car was 75 km/hr over 4 hours. b)the velocity of a car reduced from 50 km/hr over one minute. c)the velocity of a car increased from 40 km.h to 75 km/h over 15 minutes. d)the velocity of a car was 45 km/hr at 2: 00pm and at 4: 00pm its velocity was 85 km/ht.