Never heard of this!! Please help me I had a really hard day my brain is breaking apart

See explanation

Explanation:

a) u= 60 m/s, v= 45 m/s, t = 7 secs

From;

v = u + at

a = v - u/t

a= 45 - 60/7

a = -2.14 m/s^2

b)

u = 200 m/s

v= 235 m/s

t = 30 secs

v = u + at

a = v-u/t

a = 235 - 200/30

a= 1.17 m/s^2

c)

i) Acceleration = 3 - 1/2-0 = 2/2  = 1 m/s^2

ii) The slope between 2 and 5 is zero because velocity was not changing with time.

iii) Within the time between 2 and 5 the speed remained at 3 m/s

iv) the slope between 5 and 8 is 2 - 3/8 - 5 = -1/3 = -0.33m/s^2

v) The negative slope means that velocity is decreasing with time(deceleration).

b. atoms in metallic solids are not arranged in a regular pattern

explanation:

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.