From complete stop, a car reaches a velocity of 280 km/s east in 7 seconds. what is the rate of acceleration?

a: 4 km/s
b: 7 km/s
c: 40 km/s
d: 70 km/s

(C) 40 km/s

Explanation:

Divide your km/s and your seconds.

Equation: km/s divided by seconds = acceleration

- 280 km/s divided by 7 seconds = 40 km/s acceleration

Hope this helps you

a time line cause it goes from 685 to 978

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.