48. The surface area of a cylinder is given by
... A = 2πr² + 2πrh = 2πr(r+h)
For r = 13 mi and h = 7 mi, this becomes
... A = 2π(13 mi)(13 mi + 7 mi) = 520π mi²
The surface area of the cylinder is 520π mi² ≈ 1634 mi².
49. The surface area of a rectangular prism is
... A = 2(LW + H(L+W))
For L = 20 m, W = 10 m, H = 7 m, this becomes
... A = 2((20 m)(10 m) + (7 m)(20 m + 10 m)) = 2(200 m² + 210 m²) = 820 m²
The surface area of the prism is 820 m².
50. The formula is the same as for problem 48.
For r = 10 m and h = 13 m, this becomes
... A = 2π(10 m)(10 m + 13 m) = 460π m² ≈ 1445 m²
The surface area of the cylinder is 460π m² ≈ 1445 m².
_____
When calculations are repetitive, it is convenient to let a calculator or spreadsheet do them.
Answer:
Step-by-step explanation:
The equation of a line is usually written in the form of y=mx+c, where m is the gradient and c is the y-intercept.
The product of the gradients of perpendicular lines is -1.
Gradient of given line= 3.
(Gradient of line)(3)= -1
3m= -1
m=
subst. m= into the equation:
To find the value of c, substitute a coordinate.
When x=0, y=4,
Thus the equation of the line is .
Answer:
160°
Step-by-step explanation:
-Given the angle in radians as
-We know that
-Let our angle theta be X
#We therefore equate and cross multiply:
Hence, angle θ is 160°
Answer:
81x^4+216x^3+216x^2+96x+16
Step-by-step explanation:
Answer: 0.3439
Step-by-step explanation:
Given :The last four digits for telephone numbers are randomly selected (with replacement).
Here , each position can be occupied with any of the digit independently .
Total digits = 10
Total digits other than 0 = 9
For each digits , the probability that it is not 0 =
If we select 4 digits , The probability of getting no 0 =
(By multiplication rule of independent events)
Now , the probability that for one such phone number, the last four digits include at least one 0. = 1- P(none of them is 0)
=1- 0.6561=0.3439
Hence, the probability that for one such phone number, the last four digits include at least one 0. is 0.3439 .