A solar heating system costs $25,000 to install with a yearly operating cost of $300. An electric heating system costs $6,500 to install but incurs a yearly operating cost of $4,000. How many years will pass before the total cost of the solar heating system is less than the total cost of the electric heating system? Round your answer to the nearest year, if needed. Type in your numerical answer only; do not type any words or letters with your answer.

According to a research study, parents with young children slept 6.4 hours each night last year, on average. a random sample of 18 parents with young children was surveyed and the mean amount of time per night each parent slept was 6.8. this data has a sample standard deviation of 0.9. (assume that the scores are normally distributed.) researchers conduct a one-mean hypothesis at the 5% significance level, to test if the mean amount of time parents with young children sleep per night is greater than the mean amount of time last year. the null and alternative hypotheses are h0: μ=6.4 and ha: μ> 6.4, which is a right-tailed test. the test statistic is determined to be t0=1.89 using the partial t-table below, determine the critical value(s). if there is only one critical value, leave the second answer box blank.

Factor 15x^3 - 5x^2 +6x-2 by grouping. what is the resulting expression

Tiene pendiente -4 y pasa por el punto (-3,-2) encuentre la ecuación de la recta