1. chemistry

Calculate number of electrons present in 9.5g of PO4^3-

2. Pre-Algebra

Identify the underlined place in 83.5851. Then round the number to that place. A. thousandths; 83.58 B. hundredths; 83.59 C. hundredths; 83.58 D. thousandths; 83.59 A?

3. Chemistry

alculate the amount of energy released in the formation of one mole of MgSe bonds (not lattice energy). The radius of the magnesium ion is 0.65 Å, and the radius of the selenide ion is 1.98 Å. Note that 1Å=10−10m

4. Physics

What mass would you hang on the right side of the system in the figure to balance it -- that is, to make the clockwise and counterclockwise torques equal? (Let x1 = 33 cm and x2 = 12 cm.)

5. Maths

In class 8m, there are 27 pupils. There are twice as many boys as girls. How many boys are there?

6. physics

4N force applied on a body mass 20kg then calculate work done in 3sec?

7. Math

An only son inherited a 3/4 hectare lot. He decided to build a 40-door condominium on the lot. The floor are of the units is uniform and the total floor area of the entire condominium is 1/5 less than the area of the lot to provide for certain amenities.

8. physics

Cliff and Will are carrying a uniform 2.0m board of mass 75kg. Will is supporting the board at the end while cliff is 0.6m from the other end as shown in the following figure. Cliff has attached his lunch to his end of the board, and the tension in the

9. Calculus

Sand falls from a conveyor belt onto a conical pile at a rate of 6ft/mi^3. The radius of the base is always equal to two-thirds of the pile’s height. At what rate is the height of the pile changing when the radius of the base of the pile is 2 ft? I

10. Chemistry

An element crystallizes in a body centered cubic unit cell. The radius of this element is 2.20A , and the density is .991 g/cm^3. how many moles of atoms are within one unit cell?

11. counseling

Which of the following statements is most accurate with regard to Piaget's theory?

12. MATH

Find the total surface area of a hexagonal prism 6ft tall with a regular base measuring 9ft on each and an apothem of length 7.8ft

13. math

an outfit consists of skirt and a blouse. if there are 6 skirts and 8 blouses from which to choose, then how many different outfits are possible? we assume that any possible combination can be worn together.

14. Prealgebra/probability

A coin is tossed three times. Use a tree diagram to find the number of possible outcomes that could produce exactly two heads. I don't know how to write out a tree diagram on here, but I think this one is heads -> heads, tails -> heads, heads -> tails? A

15. writing skills

"Whether you marry or not" goes an old saying,"your sure to regret it." (2)Today,however, psychologists are trying to reduce the regret spouses may feel about their marital situations.(3)One of the approaches taken by these psychologists has been to

16. Physics

A car comes to a stop in 6s from a velicity of 30m/s. what is its acceleration? At the same acceleration, how long would it take the car to come to a stop from a velocity of 40m/s?

17. Computer science

While you can pass only one argument into a function, you can return as many values as needed from a function. True False A library function saves time for the programmer because it allows for code reuse. True False Each function should be flowcharted

18. Math

5/8 of the students in my class were boys. When 6 girls joined the class, the number of boys equaled the number of girls. How many students were in my class then? "What's the formula for this problem?"

19. writing skills

Sentence 8:In fact,most researchers beleive that the ability to discuss problems may be the single most important ingredient in a happy marriage. What correction should be made to this sentence? 1. remove the comma after fact 2. change the spelling of

20. writing skills

Sentence 9: Moreover,how couples discuss their problems was equally important. what correction should be made to this sentence? 1. remove the comma after moreover 2. change discuss to discussed 3. replace their with there 4. change was to were 5. change

21. writing skills

Sentence 5: In particular,couples planning to marry may lower the chance of divorse by comparing their relationship to thoses of happily married couples. What correction should be made to this sentence? 1. remove the comma after particular 2. change

22. Physics

The terminal voltage of a battery is 5.0V when 0.55A current is drawn from it, whereas the terminal voltage is 5.7V when a current of 0.180A is drawn. The emf of the battery is? The formula I used was V_(ab) = Emf - I*r First finding the r by taking the

23. physics

A flywheel is rotating at speed of 1200 rpm its angular acclaration is 4 rad/s how many rotation it will be done before coming to rest

24. writing skills

Sentence 3: One of the approaches taken by these psychologists has been -------- to investigate the foundations for a happy marriage Which of the following is the best way to write the underlined portion of this sentence? If you think the original is the

25. english

Studying and analyzing others’ speeches help us to be better

26. maths

the diameter of a biycle wheel is 49 cm. how far will it travel in 50 revolutions?

27. writing skills

Sentence 7: Sexual compatibility, for one thing,doesn't seem to be as important as earlier researchers thought; the ability to discuss problems, on the other hand, is. If you rewrote sentence 7 beginning with For one thing, despite what earlier

28. Physics

In the figure, a small 0.125 kg block slides down a frictionless surface through height h = 0.958 m and then sticks to a uniform vertical rod of mass M = 0.250 kg and length d = 2.32 m. The rod pivots about point O through angle θ before momentarily

29. writing skills

Sentence 12: In short, the best predictor of a happy marriage may simply be this: that the man and woman are able to communicate openly and productively before the marriage even takes place. What correction should be made to this sentence? 1. remove the

30. chemistry

You need to make a 300 ml of a .37M Na2 SO4 solution. How much Na2 So4 should you weigh out?

31. Biology

A tabacoo plant hetrozygous for recessive trait of albunism is selfed and 1200 seeds are ontained. How many seedlings obtained from such seeds will have prevent genotype. 1) 900 2) 300 3) 600 4) 1200

32. Math

In a group of 95 students , the ratio of students who like mathematics and science is 4:5 . if 10 of them like both the subjects and 15 of them like none of the subjects then by drawing a venn diagram,find how many of them like only mathematics and how

33. math

In a school of 960 pupil,48 were absent on a day. Calculate the percentage absent that day?

1) You have a protein at 20 ug/ml. Its MW =10,000. What is the concentration in molarity? Show work please! 2) You are asked to make 30 mL of a solution at 0.03M using the 0.10M stock solution. How many mililliliters of water do you use to make this

35. Physics

Find the torque on the meter stick for each situation. Ignore the mass of the meter stick. At 1/2 meter there is a 1000g weight. At 1 meter on the same stick there is a 500g weight. What is the torque? Not understanding how to come up with this answer.

36. Physics

I've tried everything and can't come up with the correct answer. Help! A liter of water has a mass of 1 kg and the mass of a water molecule is 18 amu. How many molecules of water are there in 4 L of water?

37. math

Find the equation of the line passing through (-1 , -4) and parallel to -7x+6y=8 slope intercept

38. Biology

1. When and where was the first cell born? How did it happen? 2. What are the circumstances that make the appearance of the cell in this earth? 3. What are the differences between prokaryotic and eukaryotic cell? How about plant and animal cell?

39. Math

A certain amount of money is equally divided between some persons .If there were 8 persons more each would have got one rupee less. The number of the person and the amount are?

40. Physics

I've looked at other questions posted like this and can't understand the problem or any of the answers. Could someone please show how to find for Cliff and Will? Cliff and Will are carrying a uniform 2.0m board of mass 75kg. Will is supporting the board at

41. math

Write the decimal as a fraction ir mixed number. 0.89

42. Maths

A balloon (in a shape of a sphere) is inflated with helium at a constant rate of 125 cm^3/s. Calculate the rate of increase of the diameter when the volume is 2000 cm^3.

43. math

if 20 students are present out of 50 studentsin class. how many percent of absent?

44. Sociology

What are the major differences between a functionalist or a conflict theorist when it comes to social class inequality?

45. math

Put parentheses for 6 + 1 × 1-20 = 29 is true

46. CHEMISTRY

USING DOT (.) AND CROSS (x) DIAGRAM SHOW THE BONDING IN THE COMPOUND FORMED WHEN HYDROGEN AND OXYGEN COMBINE

47. math

one third of which number must be subtracted from 7/11 to give 24/25

48. math

a fish with a mass of 4kg causes a fishing pole to bend 10cm. if the amount of bending (b) varies directly as the mass (m), how much will the pole bend for a 7 kg of fish

49. Maths

I am an even number between 65 and 75. My ones digit is greater than my tens digit. Who am I?

50. Math

Find the equation of a straight line that is parallel to y=4x+1 and passes through (7,5)

51. Economics

The Southern Tree Trimming Corporation reported an accounting profit of \$35,000 and a normal rate of return of 15 percent on capital and enterprise of \$30,000. The opportunity cost of labor is \$15,500. What is the economic profit? \$110,500 X \$19,500

52. Physics

An ion beam has a cross-sectional of 2.5 mm^2 and the charge delivered by it to a target can be expressed as q(t)=(.12 C/s^3)t^3 + (.24 C/s^2)t^2 - .45 C. Calculate the current density in the beam at t = 3.0 seconds. I used an integral from 0 to 3s. and

53. Calculus

A spider is descending vertically at a rate of 0.5 cm/sec. A lizard sits patiently on the ground at a spot 15 cm feet from the shadow of the spider (assume the shadow is directly below the spider). At what rate is the spider’s angle of elevation, θ,

54. math

find the equation of the line with slope 8 and passing through (-5 , -6 ) slope intercept form

55. math

Find the equation of a line pass through (-2, 5) and ( 3,4 )

56. Sociology

If you could make changes with regard to our social class stratification system, what changes would you make and why?

57. maths

The students standing in a straight line , holding some marbles , which are in A.P. The sum of marbles of first 8 students is 128. 3 times the difference of marbles of 2nd and 5th place students is 36 , find the A.P.

58. math

Mario's age is thrice the age of Martin. If the sum of their ages is 80 , how old are they?

59. math

the perimeter of a rectangle is 270 meters. find its dimension if the width is 3/4 of its length.

60. Maths

Which fraction is the largest 3/4, 31/50 or 17/40

61. college algebra

A study found that athletes who rested after exhausting exercise had half life of lactic acid removal about 23 minutes. How long would it take to remove 90% of the lactic acid?

62. maths

In the school 4/5 of the students are boys and the no of girls is 100.find the no of boys?