多选题If 4 more than twice n is a negative number and 6 more than n is a positive number, which of the following numbers could be the value of n? (Select all such numbers.)A-5B4C-3

The engine has more than 300（ ）,made of a number of different materials.

A.compositions
B.ingredients
C.compounds
D.components

I understand ____ preparation that staff must put in under pressure to meet the deadline.

A.more than the enormous amount of
B.better than most the enormous number of
C.better than most the enormous amount of
D.fewer than the number of

The traditional way of allocating a single channel among multiple competing users is to chop up its ( ) by using one of the multiplexing schemes such as FDM (Frequency Division Multiplexing). If there are N users, the bandwidth is divided into N equal-sized portions, with each user being assigned one portion. Since each user has a private frequency ( ), there is no interference among users.When there is only a small and constant number of users, each of which has a steady stream or a heavy load of ( 本 题 ), this division is a simple and efficient allocation mechanism. A wireless example is FM radio stations. Each station gets a portion of the FM band and uses it most of the time to broadcast its signal.However, when the number of senders is large and varying or the traffic is ( ), FDM presents some problems. If the spectrum is cut up into N regions while fewer than N users are currently interested in communicating, a large piece of valuable spectrum will be wasted. If more than N users want to communicate, some of them will be denied ( ) for lack of bandwidth.?

A. traffic
B. date
C. bursty
D. flow