9x squared - 6x - 6x + 4
9x squared - 12x + 4
The correct answer is
9x^2/10y^3
It’s (-8z^2 +8x +4y -2z)
Hope it helps
Answer:
a
The null hypothesis is 
The alternative hypothesis is 
b
The sample proportion is 
Step-by-step explanation:
From the question we are told that
The sample size is n = 546
The number of people that use a laptop overnight is 
The population proportion is 
Generally
The null hypothesis is 
The alternative hypothesis is 
Gnerally the sample proportion is mathematically represented as

=> 
=> 