# Posts by YUMI

Total # Posts: 10

**finance**

Starting a year from now and making 10 yearly payments, Pierre would like to put into a retirement account enough money so that, starting 11 years from now, he can withdraw $30000 per year until he dies. Pierre is confident that he can earn 8% per year on his money for the ...

**Algebra**

In an expedition to seize his enemy's elephants, a king marched 2 yojanas the first day. Say, intelligent calculator, with what increasing rate of daily march did he proceed, since he reached his foe's city, a distance of 80 yojanas, in a week? my answer is 22/7 but my...

**pre-calculus**

proving that the statements are true for all natural numbers 1+2+3+....+n=n(n+1)/2 i don't understand when trying to prove that P(k+1) = 1+2+3+...+k+k(k+1)= 1/2 how do you do this step???

**pre-calculus**

the foci of an ellipse are (0,2) (0,-2) and the eccentricity is 1/2. determine the equation of the ellipse. write your answer in standard form.

**physics**

a medtech student pushes a 30kg carton of books across the floor of her dormitory by exerting a constant force of 185 N at an angle of 37 degrees with the horizon. If the opposing force of friction is 70 N, how much work does she do as she moves the carton 4 m in 15 s? What ...

**Chemistry**

A buffer is prepared by mixing 205 mL of .452 M HCl and .500 L of .400 M sodium acetate. Ka =1.80 x 10^-5 I got the pH is 4.79 but i can't figure out the grams of KOH the problem says how many grams of KOH must be added to .500 L of the buffer to change the pH by .125 ...

**math**

How many different ways can 50 players in a marching band be arranged in rectangle arrangemnts?

**CHEMISTRY**

what is the product of: 1. acetic acid + copper(II) sulfate 2. potassium phosphate + ammonium chloride 3. chromium(III) nitrate + ammonia(aqueous) please help me!

**chemistry**

is it C?

**Science**

What is the current in the 30-ohm heating coil of a coffee maker that operates on a 120-volt circuit? Would be 120/30?