It’s 60 degrees so the first one
Answer:
4 mph
Step-by-step explanation:
The average speed of an object is given by the total distance covered by the time taken:

where
d is the total distance covered
t is the time taken
in the first part, the person runs for 0.4 hours at a speed of 7 mph, so the distance covered in the 1st part is

Then the distance covered in the second part is
, so the total distance is
(1)
The total time elapsed is 0.4 hours (first part) + 0.8 hours (second part), so

So we can write the average speed as
(1)
We want the average speed to be 5 mph,
v = 5 mph
Therefore we can rearrange eq.(1) to find d2:

And therefore, the speed in the second part must be

Answer:
4
Step-by-step explanation:
just put -5 to x
|-4|=4
Answer:
2cm of Rainfall
Step-by-step explanation:
When the no. of mosquitoes is the highest the slope of graph will be zero
so if we differentiate this function and equate to zero we can find the rainfall amount that gives maximum number of mosquitoes in centimetres.
m(x)= -x²+4x
differentiate
d(x)/d(m(x))= -2x+4
equate to zero
-2x+4=0
2x=4
x=2
answer: 2 cm of rain