在ORACLE中，rank()函数和dense_rank()函数的差别是（选一项） A: rank函数和dense_rank函数都没有跳跃 B: rank函数和dense_rank函数都有跳跃 C: rank函数有跳跃 dense_rank函数没有跳跃 D: rank函数没有跳跃 dense_rank函数有跳跃

词汇与结构 Warm air is less dense than cool air, and _____ air is less dense than dry air.

‎If A and B are m × n matrices then have the same rank, then the rank of AB must equal the rank of BA.‌‎‌

This is a () machine. A: multilateral B: sluggish C: dense D: sophisticated

Macrophages would be most abundant in which of the following tissues? A: Dense regular connective tissue B: Loose connective tissue C: Brown adipose tissue D: Dense irregular connective tissue

以下语句错误的是() A: LECT rank, AVG(salary) FROM people HAVING AVG(salary) > 1000 GROUP BY rank; B: SELECT rank, AVG(salary) FROM people GROUP BY rank HAVING AVG(salary) > 1000 C: SELECT rank, AVG(salary) FROM people HAVING AVG(salary) > 1000 GROUP BY rank; D: SELECT AVG(salary) FROM people GROUP BY rank HAVING AVG(salary) > 1000; E: SELECT rank, AVG(salary) FROM people GROUP BY rank WHERE AVG(salary) > 1000;

Let A be an m×n matrix, then ( ). A: AAT =ATA. B: if rank(A) = m, then AT A is invertible. C: if rank(A) = n, then AAT is invertible. D: if rank(A) = n, then AT A is invertible.

The lowest naval officer rank is ______ , while the lowest army officer rank is ______ .(全部小写)

The area was covered in () jungle. A: diverse B: dense C: indigenous D: sluggish

The air is less dense on a hot humid day than a cool dry day.