express the following using prefixes: (a)1×10^6volts

fostina chiko

2×10^-6metres . question 2:how many nanoseconds are there in 1.00year

Do you mean
Milli (m) - 1/1000
kilo (k) = 1,000,
Mega (M), = 1,000,000
Etc?
Look here https://en.wikipedia.org/wiki/Metric_prefix
The answer to this one is on there - but ask again if you can't work it out.
:)

Tabitha Farrant