Me answer this. riddle: i am the most basic building block in geometry. i look like a dot but you actually can't see me, unless you "see" me in your mind. although i am nothing, 2 of me makes a 1-dimensional being and 3 of me, not on the same line, make a 2-dimensional being! what am i?

2-digit numbers less than 91 which are 1 less than a multiple of 10

The long jump record, in feet, at a particular school can be modeled by f(x) = 19.6 + 2.5ln(x + 1) where x is the number of years since records began to be kept at the school. what is the record for the long jump 11 years after record started being kept? round your answer to the nearest tenth.

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling