If he had left earlier, it wouldn't have got dark. О He left earlier.
О He didn't leave earlier.
О It got dark.

If I had known it was your birthday, I would have bought you a present.
О I knew it was your birthday.
Ο I didn't buy you a present.
Ο I didn't know it was your birthday.

If I hadn't studied hard at university, I would have such a good job.
Ο I worked hard at university.
Ο I have a good job.
Ο I don't have a good job.

If he had told someone where he was going, they would have looked for him.
Ο He didn't tell anyone where he was going.
Ο He told someone where he was going.
Ο They didn't look for him.

If I hadn't left my phone at home, I could call my boss.
Ο I left my phone at home.
Ο I can't call my boss.
Ο I didn't leave my phone at home.

If you had passed your driving test, you could give me a lift.
Ο You passed your driving test.
Ο You didn't pass your driving test.
Ο You can't give me a lift.

Explanation:

1.He didn't left earlier

2.I didn't know it was your birthday

3.I worked hard at the university

4.He didn't tell anyone where he was going

5.I left my phone at home

6.You didn't pass your driving test

answer: skate fast eat as$

explanation: skate fast eat as$

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation: