Which one is a true statement about exothermic reactions? a. energy from an outside source is continuously being added. b. the reaction container always feels cold. c. the reactants have more heat energy than the products. d. more heat is given off than is put into the reaction

A0.580-kg rock is tied to the end of a string and is swung in a circle with a radius of 0.500 meters. the velocity of the rock is 4.50 m/s. what is the centripetal force acting on the rock? 15.5 n 5.22 n 69.8 n 23.5 n

A10nc charge sits at a point in space where the magnitude of the electric field is 1500 n/c. what will the magnitude of the field be if the 10 nc charge is replaced by a 20 nc charge? assume the system is big enough to consider the charges as small test charges.

7. see worksheet 1 for values of variables x1, x2 and x3 and answer the following questions: a. for each variable find the mean, median, coefficient of skewness, range and population standard deviation. b. compared to variable x1, how are the mean and median affected by extreme values (outliers) seen in x2 and x3. c. is the median or mean the better measure of location for x2 and x3? explain. d. explain the differences in the magnitudes of the skewness coefficients for the three variables. e. what is the relationship between the range and standard deviation looking across the three variables?