A scuba diver descended from an elevation of 0 feet to an elevation of -35 feet in 7 seconds. What integer represents the diver's average rate of elevation change in feet per second?

Acentral angle measuring 160 degrees intercepts an arc in a circle whose radius is 4. what is the length of the arc the circle formed by this central angle? round the length of the arc to the nearest hundredth of a unit. a) 4.19 units b) 6.28 units c) 12.57 units d) 12.57 square units