1. Science

400cm^3 of a gas x diffuse through a porous pot in 2 minutes. calculate the rate at which x diffuse

2. math

The length of a rectangle is 5cm longer than the its breadth. Find the length and breadth if the perimeter is 26 cm

3. Math

for what values of theta (0 < theta < 2pi) do maximum r values occur on the graph the polar equation r = 4-3 sin 3 theta

4. Algebra

Using the Summation formula for this sequence what is S12 for 4+8+16+... I don’t know how to do this at all Thanks in advance !

5. PHYSICS

If 32 g of kerosene of density 0.80 g/cm^3 are mixed with 8 g of water. What is the density of the resulting mixture

6. Algebra

Find the sum of the following series 15 ∑(3n-7) n=1 I got 9 355 and 255 ∑

27. biology

1. All the habitats that make up a forest, river, or desert are called an ________________. 2. The __________ and non-__________ parts of an ecosystem are all interconnected. 3. Living ______________ rely on the abiotic, or ______________, parts of the

28. Calculus

I know that this problem is an optimization problem, and have been going through that section in my textbook. I feel like I understand the examples but am unsure how to begin with this problem or if I am on the right track with my calculations. Any

29. math

Goran is driving to Philadelphia. Suppose that the distance to his destination (in miles) is a linear function of his total driving time (in minutes). Goran has 68 miles to his destination after 28 minutes of driving, and he has 53.6 miles to his

30. science

An unknown element X forms a compound with bromine: XBr. Predict the chemical formula of the compound that element X makes with oxygen. Justify your answer.

31. math

Suppose that the weight (in pounds) of an airplane is a linear function of the amount of fuel (in gallons) in its tank. When carrying 18 gallons of fuel, the airplane weighs 2199 pounds. When carrying 44 gallons of fuel, it weighs 2342 pounds. How much

32. English

What are some of the conflicts Mrs. Frank experienced during "The Diary of Anne Frank"? Internal and external. Also, how did Mrs. Frank change throughout the story? (Note that I changed your screenname to an acceptable name. Please use this name or another

33. Math

A triangle has an area of 16 feet. The height is 8 feet. What is the length of the base?

34. algebra

trapeziod has an area of 1575 cm2 which equation could you solve to find the height of the trapeziod

What does Angel robed in spotless white.

36. Chemistry

Calculate the cell potentials for the following voltaic cells: 2Al (s) + 3Cu 2+ (aq) → 2Al 3+ (aq) + 3Cu (s) 3Mg (s) + 2Al 3+ (aq) → 3Mg 2+ (aq) + 2Al (s) Mg (s) + Cu 2+ (aq) → Mg 2+ (aq) + Cu (s)

37. Social studies

Many countries in the region have large oil reserves but little water. How does this situation affect these countries?

38. Pre-Calculus

Green plants live in the ocean at maximum and minimum depths described by the absolute value equation |15-d|-15=0, where d is depth, in meters. Graph the equation on a number line to determine the maximum and minimum depths at which green plants live in

39. math

HELP P(7) a 1/7 b 1/8 c 3/8 d 7/8**

40. Math

I need help a little bit on my math. 1. 6> - 2/3(7x-2) 2. -1/3(x - 9) + 4 < - 2 3. -1/4 x - 8 < 3/4

41. algebra

What is: 3/4n - 18 = 1/4n - 4?

42. music

Which of the following is true about a harpsichord? A. A harpsichord has a wide range of dynamics. B. A harpsichord is still widely used today. C. A harpsichord has a very loud or very soft sound. D. A harpsichord creates sound by strings being plucked.

43. math

A cup of cereal has 12 grams of fiber,which is 40% of the recommended amount.

44. math

where can you put brackets to make this equation true? 2/5 + 2/3 ÷ 4/5 + 1 2/3 = 3

45. math

how do I put -27x=-9y-45 in slope-intercept form?

46. Maths

If A=1+1/[1+2]+1/[1+2+3]+.....+1/[1+2+3+....1000] and B=1+[3/4]+[9/(16×2!)]+[27/(64×3!)]+...+[3⁹⁹/(4⁹⁹×99!)]+...if the value of "B" converges. How do i find [A²+B²]?

47. math

Natalia finishes 2/3 of her homework in 3/4 hours. how long will it take her to finish all of her homework?

48. Biology

Predict: Acromegaly is a syndromes of excessive secretion of growth hormone (hypersomatotropism) that are nearly always due to a pituitary adenoma. What effects would acromegaly have on an individual?

49. history

How did the Crusades serve as the historical context for the Plague? (How did the Crusades lead to the Plague?)

50. math

How many 4 digit codes (0-9) no repetition and 5 has to be the first digit. 1 x 9 x 8 x7 first digit =5 one choice now 9 digits left. Right? Now I am stuck. First digit has to be 5 can have repetition, but same number cannot be next to each other. 5757 or

51. Math

If you flip a coin 3 times and roll a standard number cube. What is the probability you get 3 heads and roll a 1. Write your answer in a reduced fraction

52. math

what is r/3-4=11 1. r=45 2. r=35 3. r=33 4. r=28

53. math

Violet has 8\frac{1}{3} 3 1 ​ cups of dough to make dumplings. If she uses \frac{3}{4} 4 3 ​ cup of dough for each dumpling, how many whole dumplings can Violet make?