Answer:
C. The 6th term is positive/negative 80
Step-by-step explanation:
Given
Geometric Progression


Required

To get the 6th term of the progression, first we need to solve for the first term and the common ratio of the progression;
To solve the common ratio;
Divide the 7th term by the 5th term; This gives

Divide the numerator and the denominator of the fraction by 40
----- equation 1
Recall that the formula of a GP is

Where n is the nth term
So,


Substitute the above expression in equation 1
becomes


Square root both sides

r = ±
Next, is to solve for the first term;
Using 
By substituting 160 for T5 and ±
for r;
We get


Multiply through by 16



Now, we can easily solve for the 6th term
Recall that the formula of a GP is

Here, n = 6;



r = ±
So,
or 
or 
or 
±80
Hence, the 6th term is positive/negative 80
Answer: B
Step-by-step explanation:
Answer:
f = 11
Step-by-step explanation:
Lateral is 13.8cm
Total surface area is 32cm
The answer is B
sin=Opposite/Hypotenuse
sin=28/100
Divide numerator and denominator by 4
sin=7/25
Cosine=adjacent/hypotenuse
cos=96/100
Divide numerator and denominator by 4
cos=24/25
Tangent=opposite/adjacent
tan=28/96
Divide numerator and denominator by 4
tan=7/24