Step-by-step explanation:
t8 = a1 + (n - 1)*d
t8 = 17
17 = a1 + 7*d
t12 = 25
25 = a1 + 11d
17 = a1 + 7d Subtract
8 = 4d Divide by 4
8/4 = 4d/4
2 = d
17 = a1 + 7d
17 = a1 + 7*2
17 = a1 + 14 Subtract 14
3 = a1
Sum 20 terms
The 20 term = a1 + 19*2
The 20 term = 3 + 38
= 41
Sum = (a1 + a20) * 20 / 2
Sum = (3 + 41)* 20/2
Sum = 44 * 10
Sum = 440
Answer:
Hydrostatic Force = 35.28KN
Step-by-step explanation:
To solve this question, let's consider integrating the hydrostatic force from the top of the triangle to the bottom.
Formula for a thin horizontal slice of the triangle the force is;
δF=ρgxwδx
Where w is width of triangle; ρ is density of water and g is acceleration due to gravity
At depth x, the width of the triangle is w=2/3x.
Thus, F = (3,0)∫)ρgxwδx
=(2/3)ρg[(3,0)∫)x²δx]
= integrating, we have;
F = (2/3)ρg[(3³/3) - (0³/3)]
F = (2/5)ρg [27/3] = (2/5)(1000)(9.8)(9) = 35280 N = 35.28 KN
Answer:
D. Only one cleaning product was asked about in the survey.
Any given company can use more than one cleaning product or even use a combination of different cleaning products. The question was not specific enough, since it should have probably asked which cleaning products are used and which ones are used more frequently.
Step-by-step explanation:
the other options are wrong because:
- A. Only 50 cleaning services were surveyed. ⇒ This actually would increase the validity of the claim because it satisfies the the condition for a valid confidence interval [np and n(1 - p) are larger than 10]-
- B. Cleaning services were selected at random. ⇒ This actually would increase the validity of the claim.
- C. A well-known company conducted the survey. ⇒ This actually would increase the validity of the claim.
A plane that has more than one agent