Answer:
257 is prime.
Step-by-step explanation:
To evaluate if a number is prime, we just need to evaluate it for the prime numbers that are equal or lesser than the said number's square root.
In this case, √257 = 16.03 so we just need to see if 257 is divisible by <u>2, 3, 5, 7, 11 and 13</u> (the prime numbers that come before 16)
- 257 is odd, so it is not divisible by 2.
- The sum of its digits is 14, therefore, it is not divisible by 3.
- 257 ends in 7, therefore it's not divisible by 5.
- 257/ 7 = 36.71 so it's not divisible by 7.
- 257/ 11 = 23.36 so it's not divisible by 11
- Finally 257 / 13= 19.76 so it's not divisible by 13.
Therefore, 257 is prime.
For the volume of triangular prism, volume = 0.5xaxbxc
=0.5x10x7x6
=210cm^3
Answer:
Option B. 
Step-by-step explanation:
we know that
The area of a triangle is equal to

we have


Convert mixed numbers to an improper fractions


substitute the values

Answer:
Step-by-step explanation:
None of these choices is correct.
3y = 8 is an equation, not an expression. It states that "y is 8 divided by 3," which again is an equation.