# stefan

Newest questions posted by stefan-
## geography

why is Israel the only country in the region that qualifies as a developed nation? -
## History

What are the main factors that have affected the economic development in the Middle East? Explain the economic stagnation in the region. -
## math

Skip is practicing tennis serves against a wall. The distance between Skip and the tennis ball, in feet, at any time T, measured in seconds, is D(T)=-1.5|T-8|+9. which analysis of the formula is true? A. Skip is 9 feet from the wall and the ball will -
## History

I've been looking for the answers to questions on my study guide for a test I will have for a couple hours and I got a lot of them. However, there are some that I still have a hard time finding. Here are the questions. If I can be told even some of these, -
## maths

out of 10 litre a milkman sells some milk at the rate of Rs 15 perlitre and some at the rate of 12 per litre . He gets Rs 141 on selling it. Find the quantity of milk he sold at each rate. -
## maths

suresh scored 15 mareks more than ramesh in maths.if the sum of their marks in maths is 275.write the statement in linear equation in two variables -
## maths

QR is parallel to ST and PQ:QR = 2:1. Given the area of triangle PST is 18cm2, the area of triangle PQR in sq cm is? -
## Chemistry (My previous post lacked something)

Question: At STP propane (C3H8) burns in oxygen to form 2.15L of carbon dioxide and water. The question is in 4 parts. I just need the first: a)What mass of oxygen is necessary for this reaction? So far I've got 2.15 L x 1 mole /22.4 L But when I try to do -
## Chemistry

So I have the balanced equation: c3H8 +502 = 3C02 +4H20 Question: At STP propane (C3H8) burns in oxygen to form 2.15L of carbon dioxide and water. So I've got 2.15 L x 1 mole /22.4 L But when I try to do the mole ratio, I don't know what to do since the -
## Science

a sample of an unknown metal has a mass of 21.6g and a volume of 8.00cm^3 . calculate the density of the unknown metal -
## math

come si fanno le frazioni di un numero -
## Physics

Microwaves of wavelength 4.50 cm enter a long, narrow window in a building that is otherwise essentially opaque to the incoming waves. If the window is 36.5 cm wide, what is the distance from the central maximum to the first-order minimum along a wall 6.70 -
## Physics

A 2.40 m length of wire is held in an east-west direction and moves horizontally to the north with a speed of 15.1 m/s. The vertical component of Earth's magnetic field in this region is 40.0 µT directed downward. Calculate the induced emf between the -
## Physics

An eight turn coil encloses an elliptical area having a major axis of 40.0 cm and a minor axis of 30.0 cm. The coil lies in the plane of the screen and has a 6.10 A current flowing clockwise around it. If the coil is in a uniform magnetic field of 2.07 -
## Physics

An eight turn coil encloses an elliptical area having a major axis of 40.0 cm and a minor axis of 30.0 cm. The coil lies in the plane of the screen and has a 6.10 A current flowing clockwise around it. If the coil is in a uniform magnetic field of 2.07 -
## College Physics

A charge of -3.10 nC and a charge of -6.65 nC are separated by a distance of 80.0 cm. Find the position at which a third charge of +7.10 nC can be placed so that the net electrostatic force on it is zero. -
## College Physics

A charge of -3.10 nC and a charge of -6.65 nC are separated by a distance of 80.0 cm. Find the position at which a third charge of +7.10 nC can be placed so that the net electrostatic force on it is zero. -
## Physics

A nuclear power plant has an electrical power output of 1200 MW and operates with an efficiency of 31%. If excess energy is carried away from the plant by a river with a flow rate of 1.0 x 10^6 kg/s, what is the rise in temperature of the flowing water? -
## Physics

In one cycle a heat engine absorbs 530 J from a high-temperature reservoir and expels 310 J to a low-temperature reservoir. If the efficiency of this engine is 55% of the efficiency of a Carnot engine, what is the ratio of the low temperature to the high -
## question...biographies

Which is the MOST important literary element in biographies? A.Plots B.Characters C.Settings D.Point of view I believe is characters...but I just want to make sure with some one.