Whales live in seas, but they need air to breathe so that they can stay for an hour or__1__

Whales live in seas, but they need air to breathe so that they can stay for an hour or__1__
under water. Then they come __2__ to the top of the sea to breathe. Most whales eat plants __3__ as plankton. You cannot see plankton __4__ they are very small. The blue whale is the __5__ animal in the world. It can be 30 metres long. That is about as long as two buses. It can weigh as much as 100 tons. That is about as __6__ as 20 elephants!
1. A. much B. more C. many D.less
2.A. on B. underC. up D.into
3.A. suchB. so C. toD. too
4.A. soB. whenC.thatD. because
5.A. largestB. large C. largerD. bigger
6.A. heavyB. fat C. heavierD. fatter
急需!快!