The time taken by the rock will be 8.77 seconds.
<h3>What is speed?</h3>
Speed is defined as the ratio of the time distance traveled by the body to the time taken by the body to cover the distance.
Given that:-
The equation for free fall at the surface of some planet (s in meters, t in seconds) is s = 2.86t²
The time will be calculated by using the speed formula.
Speed = Distance \ Time
25.1 = 2.86t² \ t
t = 25.1 / 2.86
t = 8.77 seconds
Therefore the time taken by the rock will be 8.77 seconds.
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Answer:
(a) 7 essays and 29 multiple questions
(b) Your friend is incorrect
Step-by-step explanation:
Represent multiple choice with M and essay with E.
So:
--- Number of questions
--- Points
Solving (a): Number of question of each type.
Make E the subject of formula in 

Substitute 36 - M for E in 


Collect Like Terms


Divide both sides by -4


Substitute 29 for M in 


Solving (b): Can the multiple questions worth 4 points each?
It is not possible.
See explanation.
If multiple question worth 4 points each, then
would be:

Where x represents the number of points for essay questions.
Substitute 7 for E and 29 for M.


Subtract 116 from both sides



Make x the subject

Since the essay question can not have worth negative points.
Then, it is impossible to have the multiple questions worth 4 points
<em>Your friend is incorrect.</em>
Answer:
ye
Step-by-step explanation:
Answer:
y = (3x)/10
Step-by-step explanation:
quotient = divide
Answer:82
Step-by-step explanation:
surface area=pxh + 2xb
p=perimeter of base
h=height
b=area of base
Perimeter of base=7+7+2+2=18
height=3
base area=7x2=14
surface area=18x3+2x14
Surface area=82