Life scienceশূন্যস্থান পূরণ কর:—অ্যাডেনিন একটি ________ জাতীয় নাইট্রোজেনযুক্ত ক্ষারক।For class 10.​

Answer:

had been

taking

have been

Answer:

We use the past perfect tense when the action was completed before something in the past. And, the past perfect continuous tense is used when the action was continuing but remained incomplete. Often, when a sentence has two actions in the past, two different past tenses are used.

Here, 'but my little sister told me' is in the simple past tense, as the action was completed before her parents could finish planning the surprise party. As the action in the first clause of the sentence wasn't completed, we will use the past perfect continuous tense here.

Option A - 'Had been planned' is used in the passive voice to explain the sentence in the past perfect tense. For example, 'The party had been planned by us before anyone else could.' Thus option A is incorrect.Option B - To explain the action in the past perfect continuous tense, we need 'had + been + verb + ing'. 'Had being planning' is not correct as it has 'being'. Hence, option B is incorrect.

Option C - 'Has' is used in the present tense and not the past tense. Hence, option C is incorrect.

Option D - 'Had been planning' is used to explain the action in the past perfect continuous tense. Hence, option D is the correct answer.

'My parents had been planning a surprise party for me, but my little sister told me!'

Answer:

The Quartile Deviation can be defined mathematically as half of the difference between the upper and lower quartile. Here, quartile deviation can be represented as QD; Q3 denotes the upper quartile and Q1 indicates the lower quartile. Quartile Deviation is also known as the Semi Interquartile range.

Answer:

A railway station of its own

Answer:

आंकड़ों के एकत्रण और संकलन के आरंभ से ही उनके सारणीयन, संगठन, क्रमबद्धता और संक्रियात्मक विश्लेषण तक जब तक कि निष्कर्ष प्राप्त न हो जाए परिशुद्ध सांख्यिकीय तकनीकों का प्रयोग किया जाता है। हैं, आंकड़ों के प्राथमिक स्रोत कहलाते हैं।