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3 years ago

Puzzle #1: Return Date (Hint: no dots, no dashes, just 3 digit return date) *

Chemistry

1 answer:

Brut [27]3 years ago

7 0

The return date is 3 0 4

Explanation

In the letter, it is mentioned that the school will reopen after 29th of April. Thus, the tentative date of the school to reopen is 30th of April. The three digit return date is 3 0 4

3 0 4 because 30 is the date when the school will reopen and 4 is the month i.e., april when the school will reopen.

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I need chemistry help! How would I set up these problems?

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Answer: -

1) 8.33 minutes

2) 118.39 in/ s

180.43 m/min

10.83 km/ hr

Explanation: -

Speed of light = 3 x 10⁸ m/s

Distance of the earth from the sun= 93 million miles

We know 1 million = 1,000,000

Also 1 mile = 1609 m

Distance of the earth from the sun= 93 million miles

= 93,000,000 miles.

= 1.5 x $10^{11}$ m

Time taken = $\frac{Distance}{Speed}$

= $\frac{1.5 x [tex] 10^{11}$ m}{3 x 10⁸ m/s} [/tex]

= 500 s

= 500/ 60

= 8.33 minutes

2) Distance = 1 mile = 63360 inches

Time taken = 8.92 min

= 8.92 x 60

= 535.2 s

Speed = $\frac{distance}{time}$

= $\frac{63360 inches}{535.2 s}$

= 118.39 in/ s

Distance = 1 mile = 63360 inches = 63360 x 2.54 cm = 63360 x 2.54 x $10^{-2}$ m

Time taken = 8.92 min

Speed = $\frac{distance}{time}$

= $\frac{63360 x 2.54 x [tex] 10^{-2}$ m}{8.92 min} [/tex]

= 180.43 m/ min

1 m = 10⁻³ Km

1 min = 1/60 hour

1 m /min = 10⁻³ km/ $\frac{1}{60 hour}$

= 60/1000

=0.06 km/hr

180.43 m / min = 180 x 0.06 km / hr

= 10.93 km / hr

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Aaliya knows that sliced apples turn brown when left out in the open air. She also knows that pouring certain liquids on then wi

fenix001 [56]

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which statement best describes the equation caco3 2hcl → cacl2 co2 h2o? caco3 is a reactant; it is present before the reaction o

fomenos

Answer: $CaCO_3$ is a reactant; it is present before the reaction occurs.

Explanation:

In a chemical reaction the chemical formulas written before the arrow are described as reactants as they react together to form products which are written after the arrow.

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Thus $CaCO_3$ and HCl are reactants here whereas $CO_2$ , $CaCl_2$ and $H_2O$ are products.

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Answer:

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