4 boys and 5 girls are to form a line. In how many ways can this be done? Find also, the number of Permutations in which (a)The first two are girls, (b) The first is a boy and the last is a girl (c) the boys are together

"you know, playing tennis is healthier than watching a tennis match on television," katya remarked to her couch potato brother. in this sentence, healthier is a/an a. superlative. b. comparative. c. positive form. d. adverb.

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?

Determine domain and range, largest open interval, and intervals which function is continuous.