Помогите с английский, даю 55 б (раскрыть скобки с правильной формой глагола)

Open the brackets and put verbs into the appropriate form of conditional sentences.

1. If he (to work) so hard before the experiment, he wouldn’t have done all the calculations in so short time.

2. If an optical table was provided on a machine of this type, a more accurate figures (can be) obtained.

3. If you had visited the factory, you (to see) the new turbine.

4. If you had measured the instrument, you (to get) more exact results at the last conference.

5. If the engineer (to visit) the science conferences regularly, he would know all the latest developments.