Answer:
Step-by-step explanation:
Total surface of the cube = 6a²
= 6 * 42 * 42
= 10584 cm²
Hole that is drilled out, will make a cylinder shape in the middle of the cube
Volume of iron in the cube = Volume of cube - volume of cylinder
Volume of cube = a³
= 42 * 42 * 42
= 74088 cm³
Cylinder:
r = 14/2 = 7 cm
h = sideof the cube = 42 cm
Volume = πr²h

= 6468 cm³
Volume of iron in the cube = Volume of cube - volume of cylinder
= 74088 - 6468
= 67620 cm³
Time taken to rotate 90° is 13 seconds
<u>Explanation:</u>
Given:
To complete one revolution, the searchlight takes 52 seconds
One revolution = 360°
So,
360° is completed in 52 seconds
Time taken to complete 90° is 
= 13 sec
Therefore, time taken to rotate 90° is 13 seconds
Answer: A
Compound interest simply defined as the interest added at regular interval. Compound interested can be calculated using
Compound interest = P (1+) ^nt and Pe ^rt
P = Initial balance
r = Annual interest rate
n = Number of times the interest is compounded per year
t =Number of year money is invested
Using
Compound interest = P (1+ ) ^nt
Continuous
P= $ 8000
t = 6
r = 6.25%
=
= 0.0625
n = 1
Compound interest = 8000 (1+) ^1×6
= 8000 (1 + 0.0625) ^6
= 8000 (1.0625) ^ 6
= 8000× 1.4387
= $11,509.6
Semi- annually
P= $ 8000
t = 6
r = 6.3%
=
= 0.063
n = 2
Compound interest = 8000 (1+) ^2×6
= 8000 (1 + 0.063) ^12
= 8000 (1.063) ^12
= 8000× 1.4509
= $11,607.0
Investing $ 8000 semi-annually at 6.3% for 6 years yields greater return
Therefore the answer is (A)
Answer:
the answer is __________________ fill the blanks have fun EX
Step-by-step explanation: