Answer:
after 38.8 years it will double
correct option is D 38.8 years
Explanation:
given data
population grows rate = 1.8%
to find out
how many years will it take to double
solution
we consider here initial population is x
so after 1 year population will be = (100% + 1.8% ) x = 1.018 x
and after n year population will be = 
so it will double
2x = 
take log both side
log 2 = n log (1.018)
n = 
n = 38.853
so after 38.8 years it will double
correct option is D 38.8 years
Answer:Water is easily evaporated, and oil and grease will not evaporate.
Explanation:
Answer:
4v/3
Explanation:
Assume elastic collision by the law of momentum conservation:

where v is the original speed of car 1, v1 is the final speed of car 1 and v2 is final speed of car 2. m1 and m2 are masses of car 1 and car 2, respectively
Substitute 

Divide both side by
, then multiply by 6 we have



So the final speed of the second car is 4/3 of the first car original speed
The ratio of output force to the input force is generally the mechanical advantage of the machine.