Answer with Step-by-step explanation:
We are given that
A and B are matrix.
A.We know that for two square matrix A and B
Then, 
Therefore, it is true.
B. det A is the product of diagonal entries in A.
It is not true for all matrix.It is true for upper triangular matrix.
Hence, it is false.
C.

When is a factor of the characteristics polynomial of A then -5 is an eigenvalue of A not 5.
Hence, it is false.
D.An elementary row operation on A does not change the determinant.
It is true because when an elementary operation applied then the value of matrix A does not change.
Answer: B= -54t +367
N=-50t + 347
so in total would be 5 HOURS
Actually its A) Michael's dock would be closer because the angle opposite is smaller .
The activity type would be the input and the cost would be the output. Because there are two different costs for the same activity, this would not be a function.
Maria : 26.50 - 0.25(26.50) = 26.50 - 6.625 = 19.88
19.87 + 0.10(19.87) = 19.87 + 1.99 = 21.86
Edwin : 0.75(26.50) = 19.88
1.10(19.88) = 21.86
and if they each have $ 23, then yes, they both ave enough money to buy the book. They both were correct in their calculations. Because taking 25% off, is the same as paying 75%.....and taking the discount price and subtracting 10% from that, is the same as multiplying by 110%. So they basically worked the same problem, just in a little different way...and they both ended up with the same answer