The value of "d" is 80°
Explanation:
Cyclic quadrilaterals are the special group of quadrilaterals with all its base lying on the circumference of the circle. In other words, a quadrilateral inscribed in a circle is called a cyclic quadrilateral.
Cyclic quadrilateral are characterised by some special features such as
- Sum of opposite angles of a cyclic quadrilateral is always a supplementary angle.
- If one of the sides of a cyclic quadrilateral is produced, then the exterior angle so formed is always double of the corresponding interior angle.
Using the property 1
We find that since the quadrilateral is cyclic, opposite pairs must be supplementary
100°
+∠D must be equal to 180°
D=180°
-100°
=80°
Answer:
A) positive; added
Explanation:
Based on the reaction:
2NaHCO3(s) + 129kJ → Na2CO3(s) + H2(g) + CO2(g)
<em>2 moles of NaHCO3 requires 129kJ to produce 1 mole of Na2CO3, 1 mole of H2 and 1 mole of CO2.</em>
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That means, the energy must be added being, thus, an exothermic reaction. The exothermic reactions have ΔH >0.
Thus, right answer is:
A) positive; added
Answer:
C
Explanation:
I picked C because the plant is interacting with the sun which is a nonliving part of the environment.
A, B and D are wrong because seaweed, horses, and trees are living things.