B.
Let's simply look at each conjecture and determine if it's true or false.
A. 2n– 1 is odd if n is positive: Since n is an integer, 2n will
always be even. And an even number minus 1 is always odd. Doesn't matter
if n is positive or not. So this conjecture is true.
B. 2n– 1 is always even: Once again, 2n will always be even. So 2n-1 will always be odd. This conjecture is false.
C. 2n– 1 is odd if n is even: 2n is always even, so 2n-1 will always
be odd, regardless of what n is. So this conjecture is true.
D. 2n– 1 is always odd: 2n will always be even. So 2n-1 will always be odd. Once again, this conjecture is true.
Of the 4 conjectures above, only conjecture B is false. So the answer is B.
Using a system of equation, we have that:
a)
- x, which is the cost of on-site service.
- y, which is the cost of at-store service.
- z, which is the cost of by-mail service.
b)
The system is:



c)
The cost of one on-site repair service is of $90.
Item a:
The variables are:
- x, which is the cost of on-site service.
- y, which is the cost of at-store service.
- z, which is the cost of by-mail service.
Item b:
On-site service costs <u>3 times as much as at-store service</u>, thus:

By mail service costs <u>$10 less than at-store</u> service, thus:

Last week, the shop completed <u>15 services on-site, 40 services at-store, and 5 services by mail for total sales of $3100</u>, thus:

The system is:



Item c:
- The cost of one on-site repair service is x.
- First, replacing the first two equations into the third, we find y, and then with it we find x.






Then

The cost of one on-site repair service is of $90.
A similar problem is given at brainly.com/question/24823220
They split it 50/50 that's the answer
Answer:
1291.5km
Step-by-step explanation:
12.3*105=1291.5km
It the answer would be 51.41