Questions in Grade High-school

Questions in Grade High-school

[Open]In an arithmetic progression (A.P.), the sum of the first ten terms is -150, and the sum of the next ten terms is -550. Find the A.P.

[Open]Factor out the GCF from the expression \(7x + 49\).

[Open]Which aspects of climate are most important to forest ecosystems?

[Open]What are the factors of -72 that add up to -15?

[Open]How do you solve for \(\sin x \cos 2x + \cos x \sin 2x = 0\)?

[Open]Two dice are rolled. What is the probability that the sum of the numbers rolled is greater than or equal to 5?

[Open]What are the sine, cosine, and tangent of [tex]-495^\circ[/tex] and [tex]-\frac{20\pi}{3}[/tex]?

[Open]What percent of 48 is 2.4?

[Open]Background Info: The standard enthalpy of formation \((\Delta H^\circ_f)\) is the enthalpy change that occurs when exactly 1 mol of a compound is formed from its constituent elements under standard conditions. The standard conditions are 1 atm pressure, a temperature of 25 °C, and all species present at a concentration of 1 M. A "standard enthalpies of formation table" might look something like this: | Substance | \(\Delta H^\circ_f\) (kJ/mol) | |-----------|-------------------------------| | H(g) | 218 | | H\(_2\)(g)| 0 | | Ba(s) | 0 | | Ba\(^{2+}\)(aq) | −538.4 | | C(g) | 71 | | C(s) | 0 | | N(g) | 473 | | O\(_2\)(g)| 0 | | O(g) | 249 | | S\(_2\)(g)| 129 | Question: What is the balanced chemical equation for the reaction used to calculate \(\Delta H^\circ_f\) of BaCO\(_3\)(s)? If fractional coefficients are required, enter them as a fraction (i.e. 1/3). Indicate the physical states using the abbreviation (s), (l), or (g) for solid, liquid, or gas, respectively. Use (aq) for aqueous solution. EXPRESS ANSWER AS A CHEMICAL EQUATION. Please explain for me too!

[Open]The sum of 3 consecutive integers is 90. Find the largest integer if \( x \) is the smallest integer.