The height at time t is
h(t) = 144 - 16t²
When t = 0, then h = 144.
Therefore the height from the ground is 144 when the object is dropped.
When the object reaches the ground, h = 0.
Therefore
144 - 16t² = 0
t² = 144/16 = 9
t = 3 s
Answer:
The object reaches the ground in 3 seconds.
Answer:
false
Step-by-step explanation:
-5 is smaller than 3 not bigger.
Answer:
3 & 5
Step-by-step explanation:
Answer:
The correct options are 1, 3 and 4.
Step-by-step explanation:
We need to find the expressions whose simplified form is a rational number.
Rational number: If a number is defined in the form of p/q where p and q are integers and q≠0, then it is called a rational number.
For example: 0,2, 4.3 etc.
Irrational number: If a number can not defined in the form of p/q, where p and q are integers and q≠0, then it is called an irrational number.
First expression is

12 is a rational number.
Second expression is

is an irrational number.
Third expression is

21 is a rational number.
Fourth expression is

5 is a rational number.
Therefore, the correct options are 1, 3 and 4.